Has the HCG diet been shown to be safe and effective?

Answer From Katherine Zeratsky, R.D., L.D.

No on both counts. In fact, the Food and Drug Administration (FDA) has advised consumers to steer clear of over-the-counter weight-loss products that contain HCG. HCG is human chorionic gonadotropin, a hormone produced during pregnancy.

As a prescription medication, HCG is used mainly to treat fertility issues. HCG is not approved for over-the-counter use, nor has it been proved to work for weight loss. HCG medications are required to carry a label from the FDA noting that the medication is not effective for weight loss. Some over-the-counter HCG weight-loss products are labeled "homeopathic" — but the FDA says they're still not safe. Companies that sell over-the-counter HCG weight-loss products are breaking the law.

So why has there been so much talk about the HCG diet? Perhaps it's because the diet recommends severe calorie restriction — typically just 500 to 800 calories a day. People who follow diets so low in calories are likely to lose weight, at least in the short term. Some research has linked HCG weight-loss products to a possible increase in cancer risk. HCG might encourage the production of androgen cells, which could result in the growth of certain types of cancers.

However, diets that so severely limit calories have risks, such as gallstone formation, irregular heartbeat, limited intake of vitamins and minerals, and an imbalance of electrolytes.

Side effects have also been reported with the HCG diet and include fatigue, irritability, restlessness, depression, fluid buildup (edema), and swelling of the breasts in boys and men (gynecomastia). Another serious concern is the risk of blood clots forming and blocking blood vessels (thromboembolism).

If weight loss is your goal, there are safer ways to lose weight. Talk with your doctor or other health care provider about how to make healthy changes that lead to permanent weight loss, such as eating a balanced diet and getting regular exercise.

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Dec. 15, 2021 See more Expert Answers